7542(  1) - 12/14/96 00:54  - [  0]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      7542
                                                       Version: 1
                                                       Check-in Date: 13-Dec-1996
                                                                      18:20:27

1.Proposal Title:
The Globular Cluster Luminosity Function
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2. Scientific Category   3. Proposal For  4. Cycle
GALAXIES                    AR               7
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5. Investigators
                                                                                     Contact?
    PI: Dr. Joseph Silk                   University of California, Berkeley
   CoI: Steve Zepf                        University of California                      N
   CoI: Keith Ashman                      University of Kansas                          N

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6. Abstract

We propose to study the globular cluster luminosity function (GCLF) in order to test
models for the formation and evolution of globular cluster systems and to determine
the utility and accuracy of the peak of the GCLF as a cosmological distance
indicator. Observational evidence suggests that the GCLF may be fairly universal,
particularly once small color differences are accounted for. However, there are few
theoretical reasons why the GCLF and its underlying mass function should be
independent of metallicity, position within a galaxy, or host galaxy type and
environment. We will use data in the HST archive to test for three specific effects.
First, within individual elliptical galaxy globular cluster systems, we will compare
the GCLFs of red and blue populations to test the hypothesis that the inferred mass
function of globular clusters is independent of metallicity. Secondly, we will
utilize cases of multiple pointings in elliptical galaxies to compare the GCLF as a
function of position within early-type galaxies. Finally, we will look for trends
between the GCLF peak and other variables such as galactic environment. HST archival
data are ideal for addressing these questions because a comprehensive data set can
be composed by combining a number of completed programs, many of them aimed
primarily at studying the properties of elliptical galaxies rather than globular
cluster systems.
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  Data Distribution

  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:                                                              ,
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                                                7542(  1) - 12/14/96 00:54  - [  1]

            Summary Form for Proposal  7542

  Item                         Used in this proposal
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  Proposal Category            AR
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  Scientific Category          GALAXIES
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